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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4    Version 7.2 01-May-07
5    ---------------------
6    
7     1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
8        which is apparently normally available under Windows.
9    
10     2. Re-jig the pcregrep tests with different newline settings in an attempt
11        to make them independent of the local environment's newline setting.
12    
13     3. Add code to configure.ac to remove -g from the CFLAGS default settings.
14    
15     4. Some of the "internals" tests were previously cut out when the link size
16        was not 2, because the output contained actual offsets. The recent new
17        "Z" feature of pcretest means that these can be cut out, making the tests
18        usable with all link sizes.
19    
20     5. Implemented Stan Switzer's goto replacement for longjmp() when not using
21        stack recursion. This gives a massive performance boost under BSD, but just
22        a small improvement under Linux. However, it saves one field in the frame
23        in all cases.
24    
25     6. Added more features from the forthcoming Perl 5.10:
26    
27        (a) (?-n) (where n is a string of digits) is a relative subroutine or
28            recursion call. It refers to the nth most recently opened parentheses.
29    
30        (b) (?+n) is also a relative subroutine call; it refers to the nth next
31            to be opened parentheses.
32    
33        (c) Conditions that refer to capturing parentheses can be specified
34            relatively, for example, (?(-2)... or (?(+3)...
35    
36        (d) \K resets the start of the current match so that everything before
37            is not part of it.
38    
39    
40    Version 7.1 24-Apr-07
41    ---------------------
42    
43     1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
44        that is more "standard", making use of automake and other Autotools. There
45        is some re-arrangement of the files and adjustment of comments consequent
46        on this.
47    
48     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
49        for recursive directory scanning broke on some systems because the files
50        are not scanned in any specific order and on different systems the order
51        was different. A call to "sort" has been inserted into RunGrepTest for the
52        approprate test as a short-term fix. In the longer term there may be an
53        alternative.
54    
55     3. I had an email from Eric Raymond about problems translating some of PCRE's
56        man pages to HTML (despite the fact that I distribute HTML pages, some
57        people do their own conversions for various reasons). The problems
58        concerned the use of low-level troff macros .br and .in. I have therefore
59        removed all such uses from the man pages (some were redundant, some could
60        be replaced by .nf/.fi pairs). The 132html script that I use to generate
61        HTML has been updated to handle .nf/.fi and to complain if it encounters
62        .br or .in.
63    
64     4. Updated comments in configure.ac that get placed in config.h.in and also
65        arranged for config.h to be included in the distribution, with the name
66        config.h.generic, for the benefit of those who have to compile without
67        Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
68    
69     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
70        Weber: (1) pcre_internal.h was missing some function renames; (2) updated
71        makevp.bat for the current PCRE, using the additional files
72        makevp_c.txt, makevp_l.txt, and pcregexp.pas.
73    
74     6. A Windows user reported a minor discrepancy with test 2, which turned out
75        to be caused by a trailing space on an input line that had got lost in his
76        copy. The trailing space was an accident, so I've just removed it.
77    
78     7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
79        that is needed.
80    
81     8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
82        as "const" (a) because they are and (b) because it helps the PHP
83        maintainers who have recently made a script to detect big data structures
84        in the php code that should be moved to the .rodata section. I remembered
85        to update Builducptable as well, so it won't revert if ucptable.h is ever
86        re-created.
87    
88     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
89        pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
90        order to be able to cut out the UTF-8 tables in the latter when UTF-8
91        support is not required. This saves 1.5-2K of code, which is important in
92        some applications.
93    
94        Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
95        so as not to refer to the tables, even though these functions will never be
96        called when UTF-8 support is disabled. Otherwise there are problems with a
97        shared library.
98    
99    10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
100    
101        (a) It was defining its arguments as char * instead of void *.
102    
103        (b) It was assuming that all moves were upwards in memory; this was true
104            a long time ago when I wrote it, but is no longer the case.
105    
106        The emulated memove() is provided for those environments that have neither
107        memmove() nor bcopy(). I didn't think anyone used it these days, but that
108        is clearly not the case, as these two bugs were recently reported.
109    
110    11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
111        and Detrail to create the HTML documentation, the .txt form of the man
112        pages, and it removes trailing spaces from listed files. It also creates
113        pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
114        case, it wraps all the #defines with #ifndefs. This script should be run
115        before "make dist".
116    
117    12. Fixed two fairly obscure bugs concerned with quantified caseless matching
118        with Unicode property support.
119    
120        (a) For a maximizing quantifier, if the two different cases of the
121            character were of different lengths in their UTF-8 codings (there are
122            some cases like this - I found 11), and the matching function had to
123            back up over a mixture of the two cases, it incorrectly assumed they
124            were both the same length.
125    
126        (b) When PCRE was configured to use the heap rather than the stack for
127            recursion during matching, it was not correctly preserving the data for
128            the other case of a UTF-8 character when checking ahead for a match
129            while processing a minimizing repeat. If the check also involved
130            matching a wide character, but failed, corruption could cause an
131            erroneous result when trying to check for a repeat of the original
132            character.
133    
134    13. Some tidying changes to the testing mechanism:
135    
136        (a) The RunTest script now detects the internal link size and whether there
137            is UTF-8 and UCP support by running ./pcretest -C instead of relying on
138            values substituted by "configure". (The RunGrepTest script already did
139            this for UTF-8.) The configure.ac script no longer substitutes the
140            relevant variables.
141    
142        (b) The debugging options /B and /D in pcretest show the compiled bytecode
143            with length and offset values. This means that the output is different
144            for different internal link sizes. Test 2 is skipped for link sizes
145            other than 2 because of this, bypassing the problem. Unfortunately,
146            there was also a test in test 3 (the locale tests) that used /B and
147            failed for link sizes other than 2. Rather than cut the whole test out,
148            I have added a new /Z option to pcretest that replaces the length and
149            offset values with spaces. This is now used to make test 3 independent
150            of link size. (Test 2 will be tidied up later.)
151    
152    14. If erroroffset was passed as NULL to pcre_compile, it provoked a
153        segmentation fault instead of returning the appropriate error message.
154    
155    15. In multiline mode when the newline sequence was set to "any", the pattern
156        ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
157        This doesn't seem right; it now treats the CRLF combination as the line
158        ending, and so does not match in that case. It's only a pattern such as ^$
159        that would hit this one: something like ^ABC$ would have failed after \r
160        and then tried again after \r\n.
161    
162    16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
163        in an attempt to make files that differ only in their line terminators
164        compare equal. This works on Linux.
165    
166    17. Under certain error circumstances pcregrep might try to free random memory
167        as it exited. This is now fixed, thanks to valgrind.
168    
169    19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
170        "abc\r\n\r\n", it found an unwanted second match after the second \r. This
171        was because its rules for how to advance for /g after matching an empty
172        string at the end of a line did not allow for this case. They now check for
173        it specially.
174    
175    20. pcretest is supposed to handle patterns and data of any length, by
176        extending its buffers when necessary. It was getting this wrong when the
177        buffer for a data line had to be extended.
178    
179    21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
180        CRLF as a newline sequence.
181    
182    22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
183        out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
184        I have nevertheless tidied it up.
185    
186    23. Added some casts to kill warnings from HP-UX ia64 compiler.
187    
188    24. Added a man page for pcre-config.
189    
190    
191    Version 7.0 19-Dec-06
192    ---------------------
193    
194     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
195        moving to gcc 4.1.1.
196    
197     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
198        sys/time.h, which is documented as needed for this function. It doesn't
199        seem to matter on Linux, but it showed up on some releases of OS X.
200    
201     3. It seems that there are systems where bytes whose values are greater than
202        127 match isprint() in the "C" locale. The "C" locale should be the
203        default when a C program starts up. In most systems, only ASCII printing
204        characters match isprint(). This difference caused the output from pcretest
205        to vary, making some of the tests fail. I have changed pcretest so that:
206    
207        (a) When it is outputting text in the compiled version of a pattern, bytes
208            other than 32-126 are always shown as hex escapes.
209    
210        (b) When it is outputting text that is a matched part of a subject string,
211            it does the same, unless a different locale has been set for the match
212            (using the /L modifier). In this case, it uses isprint() to decide.
213    
214     4. Fixed a major bug that caused incorrect computation of the amount of memory
215        required for a compiled pattern when options that changed within the
216        pattern affected the logic of the preliminary scan that determines the
217        length. The relevant options are -x, and -i in UTF-8 mode. The result was
218        that the computed length was too small. The symptoms of this bug were
219        either the PCRE error "internal error: code overflow" from pcre_compile(),
220        or a glibc crash with a message such as "pcretest: free(): invalid next
221        size (fast)". Examples of patterns that provoked this bug (shown in
222        pcretest format) are:
223    
224          /(?-x: )/x
225          /(?x)(?-x: \s*#\s*)/
226          /((?i)[\x{c0}])/8
227          /(?i:[\x{c0}])/8
228    
229        HOWEVER: Change 17 below makes this fix obsolete as the memory computation
230        is now done differently.
231    
232     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
233        wrapper classes; (b) implement a new function in the C++ scanner that is
234        more efficient than the old way of doing things because it avoids levels of
235        recursion in the regex matching; (c) add a paragraph to the documentation
236        for the FullMatch() function.
237    
238     6. The escape sequence \n was being treated as whatever was defined as
239        "newline". Not only was this contrary to the documentation, which states
240        that \n is character 10 (hex 0A), but it also went horribly wrong when
241        "newline" was defined as CRLF. This has been fixed.
242    
243     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
244        was being set to -1 for the "end of line" case (supposedly a value that no
245        character can have). Though this value is never used (the check for end of
246        line is "zero bytes in current character"), it caused compiler complaints.
247        I've changed it to 0xffffffff.
248    
249     8. In pcre_version.c, the version string was being built by a sequence of
250        C macros that, in the event of PCRE_PRERELEASE being defined as an empty
251        string (as it is for production releases) called a macro with an empty
252        argument. The C standard says the result of this is undefined. The gcc
253        compiler treats it as an empty string (which was what was wanted) but it is
254        reported that Visual C gives an error. The source has been hacked around to
255        avoid this problem.
256    
257     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
258        builds of pcretest, and changed the call to _setmode() to use _O_BINARY
259        instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
260        of them did).
261    
262    10. Originally, pcretest opened its input and output without "b"; then I was
263        told that "b" was needed in some environments, so it was added for release
264        5.0 to both the input and output. (It makes no difference on Unix-like
265        systems.) Later I was told that it is wrong for the input on Windows. I've
266        now abstracted the modes into two macros, to make it easier to fiddle with
267        them, and removed "b" from the input mode under Windows.
268    
269    11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
270    
271    12. Added -help and --help to pcretest as an official way of being reminded
272        of the options.
273    
274    13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
275        and pcrecpp.cc because they annoy compilers at high warning levels.
276    
277    14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
278    
279    15. Fixed an occurrence of == in configure.ac that should have been = (shell
280        scripts are not C programs :-) and which was not noticed because it works
281        on Linux.
282    
283    16. pcretest is supposed to handle any length of pattern and data line (as one
284        line or as a continued sequence of lines) by extending its input buffer if
285        necessary. This feature was broken for very long pattern lines, leading to
286        a string of junk being passed to pcre_compile() if the pattern was longer
287        than about 50K.
288    
289    17. I have done a major re-factoring of the way pcre_compile() computes the
290        amount of memory needed for a compiled pattern. Previously, there was code
291        that made a preliminary scan of the pattern in order to do this. That was
292        OK when PCRE was new, but as the facilities have expanded, it has become
293        harder and harder to keep it in step with the real compile phase, and there
294        have been a number of bugs (see for example, 4 above). I have now found a
295        cunning way of running the real compile function in a "fake" mode that
296        enables it to compute how much memory it would need, while actually only
297        ever using a few hundred bytes of working memory and without too many
298        tests of the mode. This should make future maintenance and development
299        easier. A side effect of this work is that the limit of 200 on the nesting
300        depth of parentheses has been removed (though this was never a serious
301        limitation, I suspect). However, there is a downside: pcre_compile() now
302        runs more slowly than before (30% or more, depending on the pattern). I
303        hope this isn't a big issue. There is no effect on runtime performance.
304    
305    18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
306        newline (only possible for the last line of a file) and it was a
307        pattern that set a locale (followed by /Lsomething), pcretest crashed.
308    
309    19. Added additional timing features to pcretest. (1) The -tm option now times
310        matching only, not compiling. (2) Both -t and -tm can be followed, as a
311        separate command line item, by a number that specifies the number of
312        repeats to use when timing. The default is 50000; this gives better
313        precision, but takes uncomfortably long for very large patterns.
314    
315    20. Extended pcre_study() to be more clever in cases where a branch of a
316        subpattern has no definite first character. For example, (a*|b*)[cd] would
317        previously give no result from pcre_study(). Now it recognizes that the
318        first character must be a, b, c, or d.
319    
320    21. There was an incorrect error "recursive call could loop indefinitely" if
321        a subpattern (or the entire pattern) that was being tested for matching an
322        empty string contained only one non-empty item after a nested subpattern.
323        For example, the pattern (?>\x{100}*)\d(?R) provoked this error
324        incorrectly, because the \d was being skipped in the check.
325    
326    22. The pcretest program now has a new pattern option /B and a command line
327        option -b, which is equivalent to adding /B to every pattern. This causes
328        it to show the compiled bytecode, without the additional information that
329        -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
330        is the same as /B/I).
331    
332    23. A new optimization is now able automatically to treat some sequences such
333        as a*b as a*+b. More specifically, if something simple (such as a character
334        or a simple class like \d) has an unlimited quantifier, and is followed by
335        something that cannot possibly match the quantified thing, the quantifier
336        is automatically "possessified".
337    
338    24. A recursive reference to a subpattern whose number was greater than 39
339        went wrong under certain circumstances in UTF-8 mode. This bug could also
340        have affected the operation of pcre_study().
341    
342    25. Realized that a little bit of performance could be had by replacing
343        (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
344    
345    26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
346    
347    27. Possessive quantifiers such as a++ were previously implemented by turning
348        them into atomic groups such as ($>a+). Now they have their own opcodes,
349        which improves performance. This includes the automatically created ones
350        from 23 above.
351    
352    28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
353        lookahead was broken if it was not anchored. PCRE was mistakenly expecting
354        the first matched character to be a colon. This applied both to named and
355        numbered groups.
356    
357    29. The ucpinternal.h header file was missing its idempotency #ifdef.
358    
359    30. I was sent a "project" file called libpcre.a.dev which I understand makes
360        building PCRE on Windows easier, so I have included it in the distribution.
361    
362    31. There is now a check in pcretest against a ridiculously large number being
363        returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
364        loop, the loop is abandoned.
365    
366    32. Forward references to subpatterns in conditions such as (?(2)...) where
367        subpattern 2 is defined later cause pcre_compile() to search forwards in
368        the pattern for the relevant set of parentheses. This search went wrong
369        when there were unescaped parentheses in a character class, parentheses
370        escaped with \Q...\E, or parentheses in a #-comment in /x mode.
371    
372    33. "Subroutine" calls and backreferences were previously restricted to
373        referencing subpatterns earlier in the regex. This restriction has now
374        been removed.
375    
376    34. Added a number of extra features that are going to be in Perl 5.10. On the
377        whole, these are just syntactic alternatives for features that PCRE had
378        previously implemented using the Python syntax or my own invention. The
379        other formats are all retained for compatibility.
380    
381        (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
382            as (?P<name>...). The new forms, as well as being in Perl 5.10, are
383            also .NET compatible.
384    
385        (b) A recursion or subroutine call to a named group can now be defined as
386            (?&name) as well as (?P>name).
387    
388        (c) A backreference to a named group can now be defined as \k<name> or
389            \k'name' as well as (?P=name). The new forms, as well as being in Perl
390            5.10, are also .NET compatible.
391    
392        (d) A conditional reference to a named group can now use the syntax
393            (?(<name>) or (?('name') as well as (?(name).
394    
395        (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
396            groups (named and numbered) that are never evaluated inline, but can be
397            called as "subroutines" from elsewhere. In effect, the DEFINE condition
398            is always false. There may be only one alternative in such a group.
399    
400        (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
401            as the simple (?(R). The condition is true only if the most recent
402            recursion is that of the given number or name. It does not search out
403            through the entire recursion stack.
404    
405        (g) The escape \gN or \g{N} has been added, where N is a positive or
406            negative number, specifying an absolute or relative reference.
407    
408    35. Tidied to get rid of some further signed/unsigned compiler warnings and
409        some "unreachable code" warnings.
410    
411    36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
412        things, this adds five new scripts.
413    
414    37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
415        There were also incompatibilities regarding the handling of \Q..\E inside
416        character classes, for example with patterns like [\Qa\E-\Qz\E] where the
417        hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
418    
419    38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
420        matches an empty string, and forcibly breaks the loop. There were bugs in
421        this code in non-simple cases. For a pattern such as  ^(a()*)*  matched
422        against  aaaa  the result was just "a" rather than "aaaa", for example. Two
423        separate and independent bugs (that affected different cases) have been
424        fixed.
425    
426    39. Refactored the code to abolish the use of different opcodes for small
427        capturing bracket numbers. This is a tidy that I avoided doing when I
428        removed the limit on the number of capturing brackets for 3.5 back in 2001.
429        The new approach is not only tidier, it makes it possible to reduce the
430        memory needed to fix the previous bug (38).
431    
432    40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
433        sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
434        processing dot, circumflex, or dollar metacharacters, or #-comments in /x
435        mode.
436    
437    41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
438        report.
439    
440    42. Applied patch, originally from Ari Pollak, modified by Google, to allow
441        copy construction and assignment in the C++ wrapper.
442    
443    43. Updated pcregrep to support "--newline=any". In the process, I fixed a
444        couple of bugs that could have given wrong results in the "--newline=crlf"
445        case.
446    
447    44. Added a number of casts and did some reorganization of signed/unsigned int
448        variables following suggestions from Dair Grant. Also renamed the variable
449        "this" as "item" because it is a C++ keyword.
450    
451    45. Arranged for dftables to add
452    
453          #include "pcre_internal.h"
454    
455        to pcre_chartables.c because without it, gcc 4.x may remove the array
456        definition from the final binary if PCRE is built into a static library and
457        dead code stripping is activated.
458    
459    46. For an unanchored pattern, if a match attempt fails at the start of a
460        newline sequence, and the newline setting is CRLF or ANY, and the next two
461        characters are CRLF, advance by two characters instead of one.
462    
463    
464    Version 6.7 04-Jul-06
465    ---------------------
466    
467     1. In order to handle tests when input lines are enormously long, pcretest has
468        been re-factored so that it automatically extends its buffers when
469        necessary. The code is crude, but this _is_ just a test program. The
470        default size has been increased from 32K to 50K.
471    
472     2. The code in pcre_study() was using the value of the re argument before
473        testing it for NULL. (Of course, in any sensible call of the function, it
474        won't be NULL.)
475    
476     3. The memmove() emulation function in pcre_internal.h, which is used on
477        systems that lack both memmove() and bcopy() - that is, hardly ever -
478        was missing a "static" storage class specifier.
479    
480     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
481        containing an extended class (one that cannot be represented by a bitmap
482        because it contains high-valued characters or Unicode property items, e.g.
483        [\pZ]). Almost always one would set UTF-8 mode when processing such a
484        pattern, but PCRE should not loop if you do not (it no longer does).
485        [Detail: two cases were found: (a) a repeated subpattern containing an
486        extended class; (b) a recursive reference to a subpattern that followed a
487        previous extended class. It wasn't skipping over the extended class
488        correctly when UTF-8 mode was not set.]
489    
490     5. A negated single-character class was not being recognized as fixed-length
491        in lookbehind assertions such as (?<=[^f]), leading to an incorrect
492        compile error "lookbehind assertion is not fixed length".
493    
494     6. The RunPerlTest auxiliary script was showing an unexpected difference
495        between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
496        write a Perl script that can interpret lines of an input file either as
497        byte characters or as UTF-8, which is what "perltest" was being required to
498        do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
499        can't do is switch easily at run time between having the "use utf8;" pragma
500        or not. In the end, I fudged it by using the RunPerlTest script to insert
501        "use utf8;" explicitly for the UTF-8 tests.
502    
503     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
504        the end of the subject string, contrary to the documentation and to what
505        Perl does. This was true of both matching functions. Now it matches only at
506        the start of the subject and immediately after *internal* newlines.
507    
508     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
509        a pointer to an int instead of a pointer to an unsigned long int. This
510        caused problems on 64-bit systems.
511    
512     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
513        instance of the 'standard' template library not being so standard".
514    
515    10. There was no check on the number of named subpatterns nor the maximum
516        length of a subpattern name. The product of these values is used to compute
517        the size of the memory block for a compiled pattern. By supplying a very
518        long subpattern name and a large number of named subpatterns, the size
519        computation could be caused to overflow. This is now prevented by limiting
520        the length of names to 32 characters, and the number of named subpatterns
521        to 10,000.
522    
523    11. Subpatterns that are repeated with specific counts have to be replicated in
524        the compiled pattern. The size of memory for this was computed from the
525        length of the subpattern and the repeat count. The latter is limited to
526        65535, but there was no limit on the former, meaning that integer overflow
527        could in principle occur. The compiled length of a repeated subpattern is
528        now limited to 30,000 bytes in order to prevent this.
529    
530    12. Added the optional facility to have named substrings with the same name.
531    
532    13. Added the ability to use a named substring as a condition, using the
533        Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
534        are numbers (not recommended). Forward references are permitted.
535    
536    14. Added forward references in named backreferences (if you see what I mean).
537    
538    15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
539        pattern could run off the end of the subject. For example, the pattern
540        "(?s)(.{1,5})"8 did this with the subject "ab".
541    
542    16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
543        PCRE_CASELESS was set when matching characters that were quantified with ?
544        or *.
545    
546    17. A character class other than a single negated character that had a minimum
547        but no maximum quantifier - for example [ab]{6,} - was not handled
548        correctly by pce_dfa_exec(). It would match only one character.
549    
550    18. A valid (though odd) pattern that looked like a POSIX character
551        class but used an invalid character after [ (for example [[,abc,]]) caused
552        pcre_compile() to give the error "Failed: internal error: code overflow" or
553        in some cases to crash with a glibc free() error. This could even happen if
554        the pattern terminated after [[ but there just happened to be a sequence of
555        letters, a binary zero, and a closing ] in the memory that followed.
556    
557    19. Perl's treatment of octal escapes in the range \400 to \777 has changed
558        over the years. Originally (before any Unicode support), just the bottom 8
559        bits were taken. Thus, for example, \500 really meant \100. Nowadays the
560        output from "man perlunicode" includes this:
561    
562          The regular expression compiler produces polymorphic opcodes.  That
563          is, the pattern adapts to the data and automatically switches to
564          the Unicode character scheme when presented with Unicode data--or
565          instead uses a traditional byte scheme when presented with byte
566          data.
567    
568        Sadly, a wide octal escape does not cause a switch, and in a string with
569        no other multibyte characters, these octal escapes are treated as before.
570        Thus, in Perl, the pattern  /\500/ actually matches \100 but the pattern
571        /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
572        Unicode string.
573    
574        I have not perpetrated such confusion in PCRE. Up till now, it took just
575        the bottom 8 bits, as in old Perl. I have now made octal escapes with
576        values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
577        translate to the appropriate multibyte character.
578    
579    29. Applied some refactoring to reduce the number of warnings from Microsoft
580        and Borland compilers. This has included removing the fudge introduced
581        seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
582        a warning about an unused variable.
583    
584    21. PCRE has not included VT (character 0x0b) in the set of whitespace
585        characters since release 4.0, because Perl (from release 5.004) does not.
586        [Or at least, is documented not to: some releases seem to be in conflict
587        with the documentation.] However, when a pattern was studied with
588        pcre_study() and all its branches started with \s, PCRE still included VT
589        as a possible starting character. Of course, this did no harm; it just
590        caused an unnecessary match attempt.
591    
592    22. Removed a now-redundant internal flag bit that recorded the fact that case
593        dependency changed within the pattern. This was once needed for "required
594        byte" processing, but is no longer used. This recovers a now-scarce options
595        bit. Also moved the least significant internal flag bit to the most-
596        significant bit of the word, which was not previously used (hangover from
597        the days when it was an int rather than a uint) to free up another bit for
598        the future.
599    
600    23. Added support for CRLF line endings as well as CR and LF. As well as the
601        default being selectable at build time, it can now be changed at runtime
602        via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
603        specify that it is scanning data with non-default line endings.
604    
605    24. Changed the definition of CXXLINK to make it agree with the definition of
606        LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
607    
608    25. Applied Ian Taylor's patches to avoid using another stack frame for tail
609        recursions. This makes a big different to stack usage for some patterns.
610    
611    26. If a subpattern containing a named recursion or subroutine reference such
612        as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
613        the space required for the compiled pattern went wrong and gave too small a
614        value. Depending on the environment, this could lead to "Failed: internal
615        error: code overflow at offset 49" or "glibc detected double free or
616        corruption" errors.
617    
618    27. Applied patches from Google (a) to support the new newline modes and (b) to
619        advance over multibyte UTF-8 characters in GlobalReplace.
620    
621    28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
622        difference for some implementation of PCRE in some Windows version.
623    
624    29. Added some extra testing facilities to pcretest:
625    
626        \q<number>   in a data line sets the "match limit" value
627        \Q<number>   in a data line sets the "match recursion limt" value
628        -S <number>  sets the stack size, where <number> is in megabytes
629    
630        The -S option isn't available for Windows.
631    
632    
633    Version 6.6 06-Feb-06
634    ---------------------
635    
636     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
637        in pcreposix.h. I have copied the definition from pcre.h.
638    
639     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
640        because pcre.h is no longer a built file.
641    
642     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
643        not normally included in the compiled code.
644    
645    
646    Version 6.5 01-Feb-06
647    ---------------------
648    
649     1. When using the partial match feature with pcre_dfa_exec(), it was not
650        anchoring the second and subsequent partial matches at the new starting
651        point. This could lead to incorrect results. For example, with the pattern
652        /1234/, partially matching against "123" and then "a4" gave a match.
653    
654     2. Changes to pcregrep:
655    
656        (a) All non-match returns from pcre_exec() were being treated as failures
657            to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
658            error message is output. Some extra information is given for the
659            PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
660            probably the only errors that are likely to be caused by users (by
661            specifying a regex that has nested indefinite repeats, for instance).
662            If there are more than 20 of these errors, pcregrep is abandoned.
663    
664        (b) A binary zero was treated as data while matching, but terminated the
665            output line if it was written out. This has been fixed: binary zeroes
666            are now no different to any other data bytes.
667    
668        (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
669            used to set a locale for matching. The --locale=xxxx long option has
670            been added (no short equivalent) to specify a locale explicitly on the
671            pcregrep command, overriding the environment variables.
672    
673        (d) When -B was used with -n, some line numbers in the output were one less
674            than they should have been.
675    
676        (e) Added the -o (--only-matching) option.
677    
678        (f) If -A or -C was used with -c (count only), some lines of context were
679            accidentally printed for the final match.
680    
681        (g) Added the -H (--with-filename) option.
682    
683        (h) The combination of options -rh failed to suppress file names for files
684            that were found from directory arguments.
685    
686        (i) Added the -D (--devices) and -d (--directories) options.
687    
688        (j) Added the -F (--fixed-strings) option.
689    
690        (k) Allow "-" to be used as a file name for -f as well as for a data file.
691    
692        (l) Added the --colo(u)r option.
693    
694        (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
695            is not present by default.
696    
697     3. A nasty bug was discovered in the handling of recursive patterns, that is,
698        items such as (?R) or (?1), when the recursion could match a number of
699        alternatives. If it matched one of the alternatives, but subsequently,
700        outside the recursion, there was a failure, the code tried to back up into
701        the recursion. However, because of the way PCRE is implemented, this is not
702        possible, and the result was an incorrect result from the match.
703    
704        In order to prevent this happening, the specification of recursion has
705        been changed so that all such subpatterns are automatically treated as
706        atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
707    
708     4. I had overlooked the fact that, in some locales, there are characters for
709        which isalpha() is true but neither isupper() nor islower() are true. In
710        the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
711        and ordfeminine) are like this. This affected the treatment of \w and \W
712        when they appeared in character classes, but not when they appeared outside
713        a character class. The bit map for "word" characters is now created
714        separately from the results of isalnum() instead of just taking it from the
715        upper, lower, and digit maps. (Plus the underscore character, of course.)
716    
717     5. The above bug also affected the handling of POSIX character classes such as
718        [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
719        permanent tables. Instead, the bit maps for such a class were previously
720        created as the appropriate unions of the upper, lower, and digit bitmaps.
721        Now they are created by subtraction from the [[:word:]] class, which has
722        its own bitmap.
723    
724     6. The [[:blank:]] character class matches horizontal, but not vertical space.
725        It is created by subtracting the vertical space characters (\x09, \x0a,
726        \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
727        subtraction was done in the overall bitmap for a character class, meaning
728        that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
729        be recognized. This bug has been fixed.
730    
731     7. Patches from the folks at Google:
732    
733          (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
734          real life, but is still worth protecting against".
735    
736          (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
737          regular expressions".
738    
739          (c) pcre_scanner.cc: avoid use of std::count() because not all systems
740          have it.
741    
742          (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
743          "configure" and the latter not, in order to fix a problem somebody had
744          with compiling the Arg class on HP-UX.
745    
746          (e) Improve the error-handling of the C++ wrapper a little bit.
747    
748          (f) New tests for checking recursion limiting.
749    
750     8. The pcre_memmove() function, which is used only if the environment does not
751        have a standard memmove() function (and is therefore rarely compiled),
752        contained two bugs: (a) use of int instead of size_t, and (b) it was not
753        returning a result (though PCRE never actually uses the result).
754    
755     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
756        large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
757        returned instead of calling malloc() with an overflowing number that would
758        most likely cause subsequent chaos.
759    
760    10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
761    
762    11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
763        with this option is matched, the nmatch and pmatch options of regexec() are
764        ignored.
765    
766    12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
767        provided in case anyone wants to the the POSIX interface with UTF-8
768        strings.
769    
770    13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
771        C++ linking (needed for some HP-UX environments).
772    
773    14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
774        (unused parameter) and in the pcre_printint() function (omitted "default"
775        switch label when the default is to do nothing).
776    
777    15. Added some code to make it possible, when PCRE is compiled as a C++
778        library, to replace subject pointers for pcre_exec() with a smart pointer
779        class, thus making it possible to process discontinuous strings.
780    
781    16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
782        much the same function. They were added by different people who were trying
783        to make PCRE easy to compile on non-Unix systems. It has been suggested
784        that PCRE_EXPORT be abolished now that there is more automatic apparatus
785        for compiling on Windows systems. I have therefore replaced it with
786        PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
787        defaults to "extern" for C or "extern C" for C++, which works fine on
788        Unix-like systems. It is now possible to override the value of PCRE_DATA_
789        SCOPE with something explicit in config.h. In addition:
790    
791        (a) pcreposix.h still had just "extern" instead of either of these macros;
792            I have replaced it with PCRE_DATA_SCOPE.
793    
794        (b) Functions such as _pcre_xclass(), which are internal to the library,
795            but external in the C sense, all had PCRE_EXPORT in their definitions.
796            This is apparently wrong for the Windows case, so I have removed it.
797            (It makes no difference on Unix-like systems.)
798    
799    17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
800        of recursive calls to match(). This is different to MATCH_LIMIT because
801        that limits the total number of calls to match(), not all of which increase
802        the depth of recursion. Limiting the recursion depth limits the amount of
803        stack (or heap if NO_RECURSE is set) that is used. The default can be set
804        when PCRE is compiled, and changed at run time. A patch from Google adds
805        this functionality to the C++ interface.
806    
807    18. Changes to the handling of Unicode character properties:
808    
809        (a) Updated the table to Unicode 4.1.0.
810    
811        (b) Recognize characters that are not in the table as "Cn" (undefined).
812    
813        (c) I revised the way the table is implemented to a much improved format
814            which includes recognition of ranges. It now supports the ranges that
815            are defined in UnicodeData.txt, and it also amalgamates other
816            characters into ranges. This has reduced the number of entries in the
817            table from around 16,000 to around 3,000, thus reducing its size
818            considerably. I realized I did not need to use a tree structure after
819            all - a binary chop search is just as efficient. Having reduced the
820            number of entries, I extended their size from 6 bytes to 8 bytes to
821            allow for more data.
822    
823        (d) Added support for Unicode script names via properties such as \p{Han}.
824    
825    19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
826        matching that character.
827    
828    20. When matching a repeated Unicode property with a minimum greater than zero,
829        (for example \pL{2,}), PCRE could look past the end of the subject if it
830        reached it while seeking the minimum number of characters. This could
831        happen only if some of the characters were more than one byte long, because
832        there is a check for at least the minimum number of bytes.
833    
834    21. Refactored the implementation of \p and \P so as to be more general, to
835        allow for more different types of property in future. This has changed the
836        compiled form incompatibly. Anybody with saved compiled patterns that use
837        \p or \P will have to recompile them.
838    
839    22. Added "Any" and "L&" to the supported property types.
840    
841    23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
842        but give a compile time error if the value is greater than 0xff.
843    
844    24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
845        accidentally not being installed or uninstalled.
846    
847    25. The pcre.h file was built from pcre.h.in, but the only changes that were
848        made were to insert the current release number. This seemed silly, because
849        it made things harder for people building PCRE on systems that don't run
850        "configure". I have turned pcre.h into a distributed file, no longer built
851        by "configure", with the version identification directly included. There is
852        no longer a pcre.h.in file.
853    
854        However, this change necessitated a change to the pcre-config script as
855        well. It is built from pcre-config.in, and one of the substitutions was the
856        release number. I have updated configure.ac so that ./configure now finds
857        the release number by grepping pcre.h.
858    
859    26. Added the ability to run the tests under valgrind.
860    
861    
862    Version 6.4 05-Sep-05
863    ---------------------
864    
865     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
866        "--" to be printed when multiple files were scanned, even when none of the
867        -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
868        consider it to be a bug, and have restored the previous behaviour.
869    
870     2. A couple of code tidies to get rid of compiler warnings.
871    
872     3. The pcretest program used to cheat by referring to symbols in the library
873        whose names begin with _pcre_. These are internal symbols that are not
874        really supposed to be visible externally, and in some environments it is
875        possible to suppress them. The cheating is now confined to including
876        certain files from the library's source, which is a bit cleaner.
877    
878     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
879        file's purpose clearer.
880    
881     5. Reorganized pcre_ucp_findchar().
882    
883    
884    Version 6.3 15-Aug-05
885    ---------------------
886    
887     1. The file libpcre.pc.in did not have general read permission in the tarball.
888    
889     2. There were some problems when building without C++ support:
890    
891        (a) If C++ support was not built, "make install" and "make test" still
892            tried to test it.
893    
894        (b) There were problems when the value of CXX was explicitly set. Some
895            changes have been made to try to fix these, and ...
896    
897        (c) --disable-cpp can now be used to explicitly disable C++ support.
898    
899        (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
900            backslash in a target when C++ was disabled. This confuses some
901            versions of "make", apparently. Using an intermediate variable solves
902            this. (Same for CPP_LOBJ.)
903    
904     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
905        (non-Windows) now includes $(CFLAGS) because these flags are sometimes
906        necessary on certain architectures.
907    
908     4. Added a setting of -export-symbols-regex to the link command to remove
909        those symbols that are exported in the C sense, but actually are local
910        within the library, and not documented. Their names all begin with
911        "_pcre_". This is not a perfect job, because (a) we have to except some
912        symbols that pcretest ("illegally") uses, and (b) the facility isn't always
913        available (and never for static libraries). I have made a note to try to
914        find a way round (a) in the future.
915    
916    
917    Version 6.2 01-Aug-05
918    ---------------------
919    
920     1. There was no test for integer overflow of quantifier values. A construction
921        such as {1111111111111111} would give undefined results. What is worse, if
922        a minimum quantifier for a parenthesized subpattern overflowed and became
923        negative, the calculation of the memory size went wrong. This could have
924        led to memory overwriting.
925    
926     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
927    
928     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
929        operating environments where this matters.
930    
931     4. Applied Giuseppe Maxia's patch to add additional features for controlling
932        PCRE options from within the C++ wrapper.
933    
934     5. Named capturing subpatterns were not being correctly counted when a pattern
935        was compiled. This caused two problems: (a) If there were more than 100
936        such subpatterns, the calculation of the memory needed for the whole
937        compiled pattern went wrong, leading to an overflow error. (b) Numerical
938        back references of the form \12, where the number was greater than 9, were
939        not recognized as back references, even though there were sufficient
940        previous subpatterns.
941    
942     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
943        versions of gcc, e.g. 2.95.4.
944    
945    
946    Version 6.1 21-Jun-05
947    ---------------------
948    
949     1. There was one reference to the variable "posix" in pcretest.c that was not
950        surrounded by "#if !defined NOPOSIX".
951    
952     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
953        the cross-check on the old pcre_info() function, for the benefit of the
954        cut-down version of PCRE that is currently imported into Exim.
955    
956     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
957        allocation error. I've done the easy fix, which wastes 2 bytes for sensible
958        patterns that start (?i) but I don't think that matters. The use of (?i) is
959        just an example; this all applies to the other options as well.
960    
961     4. Since libtool seems to echo the compile commands it is issuing, the output
962        from "make" can be reduced a bit by putting "@" in front of each libtool
963        compile command.
964    
965     5. Patch from the folks at Google for configure.in to be a bit more thorough
966        in checking for a suitable C++ installation before trying to compile the
967        C++ stuff. This should fix a reported problem when a compiler was present,
968        but no suitable headers.
969    
970     6. The man pages all had just "PCRE" as their title. I have changed them to
971        be the relevant file name. I have also arranged that these names are
972        retained in the file doc/pcre.txt, which is a concatenation in text format
973        of all the man pages except the little individual ones for each function.
974    
975     7. The NON-UNIX-USE file had not been updated for the different set of source
976        files that come with release 6. I also added a few comments about the C++
977        wrapper.
978    
979    
980    Version 6.0 07-Jun-05
981    ---------------------
982    
983     1. Some minor internal re-organization to help with my DFA experiments.
984    
985     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
986        didn't matter for the library itself when fully configured, but did matter
987        when compiling without UCP support, or within Exim, where the ucp files are
988        not imported.
989    
990     3. Refactoring of the library code to split up the various functions into
991        different source modules. The addition of the new DFA matching code (see
992        below) to a single monolithic source would have made it really too
993        unwieldy, quite apart from causing all the code to be include in a
994        statically linked application, when only some functions are used. This is
995        relevant even without the DFA addition now that patterns can be compiled in
996        one application and matched in another.
997    
998        The downside of splitting up is that there have to be some external
999        functions and data tables that are used internally in different modules of
1000        the library but which are not part of the API. These have all had their
1001        names changed to start with "_pcre_" so that they are unlikely to clash
1002        with other external names.
1003    
1004     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1005        a different (DFA) algorithm. Although it is slower than the original
1006        function, it does have some advantages for certain types of matching
1007        problem.
1008    
1009     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1010        including restarting after a partial match.
1011    
1012     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1013        defined when compiling for Windows was sent to me. I have put it into the
1014        code, though I have no means of testing or verifying it.
1015    
1016     7. Added the pcre_refcount() auxiliary function.
1017    
1018     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1019        match before or at the first newline in the subject string. In pcretest,
1020        the /f option on a pattern can be used to set this.
1021    
1022     9. A repeated \w when used in UTF-8 mode with characters greater than 256
1023        would behave wrongly. This has been present in PCRE since release 4.0.
1024    
1025    10. A number of changes to the pcregrep command:
1026    
1027        (a) Refactored how -x works; insert ^(...)$ instead of setting
1028            PCRE_ANCHORED and checking the length, in preparation for adding
1029            something similar for -w.
1030    
1031        (b) Added the -w (match as a word) option.
1032    
1033        (c) Refactored the way lines are read and buffered so as to have more
1034            than one at a time available.
1035    
1036        (d) Implemented a pcregrep test script.
1037    
1038        (e) Added the -M (multiline match) option. This allows patterns to match
1039            over several lines of the subject. The buffering ensures that at least
1040            8K, or the rest of the document (whichever is the shorter) is available
1041            for matching (and similarly the previous 8K for lookbehind assertions).
1042    
1043        (f) Changed the --help output so that it now says
1044    
1045              -w, --word-regex(p)
1046    
1047            instead of two lines, one with "regex" and the other with "regexp"
1048            because that confused at least one person since the short forms are the
1049            same. (This required a bit of code, as the output is generated
1050            automatically from a table. It wasn't just a text change.)
1051    
1052        (g) -- can be used to terminate pcregrep options if the next thing isn't an
1053            option but starts with a hyphen. Could be a pattern or a path name
1054            starting with a hyphen, for instance.
1055    
1056        (h) "-" can be given as a file name to represent stdin.
1057    
1058        (i) When file names are being printed, "(standard input)" is used for
1059            the standard input, for compatibility with GNU grep. Previously
1060            "<stdin>" was used.
1061    
1062        (j) The option --label=xxx can be used to supply a name to be used for
1063            stdin when file names are being printed. There is no short form.
1064    
1065        (k) Re-factored the options decoding logic because we are going to add
1066            two more options that take data. Such options can now be given in four
1067            different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1068    
1069        (l) Added the -A, -B, and -C options for requesting that lines of context
1070            around matches be printed.
1071    
1072        (m) Added the -L option to print the names of files that do not contain
1073            any matching lines, that is, the complement of -l.
1074    
1075        (n) The return code is 2 if any file cannot be opened, but pcregrep does
1076            continue to scan other files.
1077    
1078        (o) The -s option was incorrectly implemented. For compatibility with other
1079            greps, it now suppresses the error message for a non-existent or non-
1080            accessible file (but not the return code). There is a new option called
1081            -q that suppresses the output of matching lines, which was what -s was
1082            previously doing.
1083    
1084        (p) Added --include and --exclude options to specify files for inclusion
1085            and exclusion when recursing.
1086    
1087    11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1088        Hopefully, it now does.
1089    
1090    12. Missing cast in pcre_study().
1091    
1092    13. Added an "uninstall" target to the makefile.
1093    
1094    14. Replaced "extern" in the function prototypes in Makefile.in with
1095        "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1096        world, but is set differently for Windows.
1097    
1098    15. Added a second compiling function called pcre_compile2(). The only
1099        difference is that it has an extra argument, which is a pointer to an
1100        integer error code. When there is a compile-time failure, this is set
1101        non-zero, in addition to the error test pointer being set to point to an
1102        error message. The new argument may be NULL if no error number is required
1103        (but then you may as well call pcre_compile(), which is now just a
1104        wrapper). This facility is provided because some applications need a
1105        numeric error indication, but it has also enabled me to tidy up the way
1106        compile-time errors are handled in the POSIX wrapper.
1107    
1108    16. Added VPATH=.libs to the makefile; this should help when building with one
1109        prefix path and installing with another. (Or so I'm told by someone who
1110        knows more about this stuff than I do.)
1111    
1112    17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1113        passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1114        match everything, including newlines. This is not POSIX-compatible, but
1115        somebody wanted the feature. From pcretest it can be activated by using
1116        both the P and the s flags.
1117    
1118    18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1119    
1120    19. libpcre.pc was being incorrectly installed as executable.
1121    
1122    20. A couple of places in pcretest check for end-of-line by looking for '\n';
1123        it now also looks for '\r' so that it will work unmodified on Windows.
1124    
1125    21. Added Google's contributed C++ wrapper to the distribution.
1126    
1127    22. Added some untidy missing memory free() calls in pcretest, to keep
1128        Electric Fence happy when testing.
1129    
1130    
1131    
1132    Version 5.0 13-Sep-04
1133    ---------------------
1134    
1135     1. Internal change: literal characters are no longer packed up into items
1136        containing multiple characters in a single byte-string. Each character
1137        is now matched using a separate opcode. However, there may be more than one
1138        byte in the character in UTF-8 mode.
1139    
1140     2. The pcre_callout_block structure has two new fields: pattern_position and
1141        next_item_length. These contain the offset in the pattern to the next match
1142        item, and its length, respectively.
1143    
1144     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1145        insertion of callouts before each pattern item. Added the /C option to
1146        pcretest to make use of this.
1147    
1148     4. On the advice of a Windows user, the lines
1149    
1150          #if defined(_WIN32) || defined(WIN32)
1151          _setmode( _fileno( stdout ), 0x8000 );
1152          #endif  /* defined(_WIN32) || defined(WIN32) */
1153    
1154        have been added to the source of pcretest. This apparently does useful
1155        magic in relation to line terminators.
1156    
1157     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
1158        for the benefit of those environments where the "b" makes a difference.
1159    
1160     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
1161        to know about it. I have put a hack into configure.in that adds in code
1162        to set GCC=yes if CC=icc. This seems to end up at a point in the
1163        generated configure script that is early enough to affect the setting of
1164        compiler options, which is what is needed, but I have no means of testing
1165        whether it really works. (The user who reported this had patched the
1166        generated configure script, which of course I cannot do.)
1167    
1168        LATER: After change 22 below (new libtool files), the configure script
1169        seems to know about icc (and also ecc). Therefore, I have commented out
1170        this hack in configure.in.
1171    
1172     7. Added support for pkg-config (2 patches were sent in).
1173    
1174     8. Negated POSIX character classes that used a combination of internal tables
1175        were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
1176        [[:^ascii]]. Typically, they would match almost any characters. The other
1177        POSIX classes were not broken in this way.
1178    
1179     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
1180        to find the match, as PCRE was deluded into thinking that the match had to
1181        start at the start point or following a newline. The same bug applied to
1182        patterns with negative forward assertions or any backward assertions
1183        preceding ".*" at the start, unless the pattern required a fixed first
1184        character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
1185    
1186    10. In UTF-8 mode, when moving forwards in the subject after a failed match
1187        starting at the last subject character, bytes beyond the end of the subject
1188        string were read.
1189    
1190    11. Renamed the variable "class" as "classbits" to make life easier for C++
1191        users. (Previously there was a macro definition, but it apparently wasn't
1192        enough.)
1193    
1194    12. Added the new field "tables" to the extra data so that tables can be passed
1195        in at exec time, or the internal tables can be re-selected. This allows
1196        a compiled regex to be saved and re-used at a later time by a different
1197        program that might have everything at different addresses.
1198    
1199    13. Modified the pcre-config script so that, when run on Solaris, it shows a
1200        -R library as well as a -L library.
1201    
1202    14. The debugging options of pcretest (-d on the command line or D on a
1203        pattern) showed incorrect output for anything following an extended class
1204        that contained multibyte characters and which was followed by a quantifier.
1205    
1206    15. Added optional support for general category Unicode character properties
1207        via the \p, \P, and \X escapes. Unicode property support implies UTF-8
1208        support. It adds about 90K to the size of the library. The meanings of the
1209        inbuilt class escapes such as \d and \s have NOT been changed.
1210    
1211    16. Updated pcredemo.c to include calls to free() to release the memory for the
1212        compiled pattern.
1213    
1214    17. The generated file chartables.c was being created in the source directory
1215        instead of in the building directory. This caused the build to fail if the
1216        source directory was different from the building directory, and was
1217        read-only.
1218    
1219    18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
1220        file. No doubt somebody will tell me if they don't make sense... Also added
1221        Dan Mooney's comments about building on OpenVMS.
1222    
1223    19. Added support for partial matching via the PCRE_PARTIAL option for
1224        pcre_exec() and the \P data escape in pcretest.
1225    
1226    20. Extended pcretest with 3 new pattern features:
1227    
1228        (i)   A pattern option of the form ">rest-of-line" causes pcretest to
1229              write the compiled pattern to the file whose name is "rest-of-line".
1230              This is a straight binary dump of the data, with the saved pointer to
1231              the character tables forced to be NULL. The study data, if any, is
1232              written too. After writing, pcretest reads a new pattern.
1233    
1234        (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
1235              compiled pattern from the given file. There must not be any
1236              occurrences of "<" in the file name (pretty unlikely); if there are,
1237              pcretest will instead treat the initial "<" as a pattern delimiter.
1238              After reading in the pattern, pcretest goes on to read data lines as
1239              usual.
1240    
1241        (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
1242              and 16-bit fields in a compiled pattern, to simulate a pattern that
1243              was compiled on a host of opposite endianness.
1244    
1245    21. The pcre-exec() function can now cope with patterns that were compiled on
1246        hosts of opposite endianness, with this restriction:
1247    
1248          As for any compiled expression that is saved and used later, the tables
1249          pointer field cannot be preserved; the extra_data field in the arguments
1250          to pcre_exec() should be used to pass in a tables address if a value
1251          other than the default internal tables were used at compile time.
1252    
1253    22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
1254        now diagnosed as an error. Previously, most of the time, a negative number
1255        would have been treated as zero, but if in addition "ovector" was passed as
1256        NULL, a crash could occur.
1257    
1258    23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
1259        new versions from the libtool 1.5 distribution (the last one is a copy of
1260        a file called libtool.m4). This seems to have fixed the need to patch
1261        "configure" to support Darwin 1.3 (which I used to do). However, I still
1262        had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
1263        workstation).
1264    
1265    24. Changed the PCRE licence to be the more standard "BSD" licence.
1266    
1267    
1268    Version 4.5 01-Dec-03
1269    ---------------------
1270    
1271     1. There has been some re-arrangement of the code for the match() function so
1272        that it can be compiled in a version that does not call itself recursively.
1273        Instead, it keeps those local variables that need separate instances for
1274        each "recursion" in a frame on the heap, and gets/frees frames whenever it
1275        needs to "recurse". Keeping track of where control must go is done by means
1276        of setjmp/longjmp. The whole thing is implemented by a set of macros that
1277        hide most of the details from the main code, and operates only if
1278        NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
1279        "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
1280        operating.
1281    
1282        To make it easier for callers to provide specially tailored get/free
1283        functions for this usage, two new functions, pcre_stack_malloc, and
1284        pcre_stack_free, are used. They are always called in strict stacking order,
1285        and the size of block requested is always the same.
1286    
1287        The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
1288        PCRE has been compiled to use the stack or the heap for recursion. The
1289        -C option of pcretest uses this to show which version is compiled.
1290    
1291        A new data escape \S, is added to pcretest; it causes the amounts of store
1292        obtained and freed by both kinds of malloc/free at match time to be added
1293        to the output.
1294    
1295     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
1296        what's available on my current Linux desktop machine.
1297    
1298     3. When matching a UTF-8 string, the test for a valid string at the start has
1299        been extended. If start_offset is not zero, PCRE now checks that it points
1300        to a byte that is the start of a UTF-8 character. If not, it returns
1301        PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
1302        this is necessary because there may be backward assertions in the pattern.
1303        When matching the same subject several times, it may save resources to use
1304        PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
1305    
1306     4. The code for checking the validity of UTF-8 strings has been tightened so
1307        that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
1308        containing "overlong sequences".
1309    
1310     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
1311        I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
1312        should have been "&", but it just so happened that all the cases this let
1313        through by mistake were picked up later in the function.
1314    
1315     6. I had used a variable called "isblank" - this is a C99 function, causing
1316        some compilers to warn. To avoid this, I renamed it (as "blankclass").
1317    
1318     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
1319        prompting; (b) run "./pcretest /dev/null" at the start of the test script
1320        so the version is shown; (c) stop "make test" echoing "./RunTest".
1321    
1322     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
1323    
1324     9. The prototype for memmove() for systems that don't have it was using
1325        size_t, but the inclusion of the header that defines size_t was later. I've
1326        moved the #includes for the C headers earlier to avoid this.
1327    
1328    10. Added some adjustments to the code to make it easier to compiler on certain
1329        special systems:
1330    
1331          (a) Some "const" qualifiers were missing.
1332          (b) Added the macro EXPORT before all exported functions; by default this
1333              is defined to be empty.
1334          (c) Changed the dftables auxiliary program (that builds chartables.c) so
1335              that it reads its output file name as an argument instead of writing
1336              to the standard output and assuming this can be redirected.
1337    
1338    11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
1339        class containing characters with values greater than 255, PCRE compilation
1340        went into a loop.
1341    
1342    12. A recursive reference to a subpattern that was within another subpattern
1343        that had a minimum quantifier of zero caused PCRE to crash. For example,
1344        (x(y(?2))z)? provoked this bug with a subject that got as far as the
1345        recursion. If the recursively-called subpattern itself had a zero repeat,
1346        that was OK.
1347    
1348    13. In pcretest, the buffer for reading a data line was set at 30K, but the
1349        buffer into which it was copied (for escape processing) was still set at
1350        1024, so long lines caused crashes.
1351    
1352    14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
1353        "internal error: code overflow...". This applied to any character class
1354        that was followed by a possessive quantifier.
1355    
1356    15. Modified the Makefile to add libpcre.la as a prerequisite for
1357        libpcreposix.la because I was told this is needed for a parallel build to
1358        work.
1359    
1360    16. If a pattern that contained .* following optional items at the start was
1361        studied, the wrong optimizing data was generated, leading to matching
1362        errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
1363        matching string must start with a or b or c. The correct conclusion for
1364        this pattern is that a match can start with any character.
1365    
1366    
1367    Version 4.4 13-Aug-03
1368    ---------------------
1369    
1370     1. In UTF-8 mode, a character class containing characters with values between
1371        127 and 255 was not handled correctly if the compiled pattern was studied.
1372        In fixing this, I have also improved the studying algorithm for such
1373        classes (slightly).
1374    
1375     2. Three internal functions had redundant arguments passed to them. Removal
1376        might give a very teeny performance improvement.
1377    
1378     3. Documentation bug: the value of the capture_top field in a callout is *one
1379        more than* the number of the hightest numbered captured substring.
1380    
1381     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
1382        in incorrectly linking with a previously installed version. They now link
1383        explicitly with libpcre.la.
1384    
1385     5. configure.in no longer needs to recognize Cygwin specially.
1386    
1387     6. A problem in pcre.in for Windows platforms is fixed.
1388    
1389     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
1390        pcretest, it used to include the size of the study block as part of its
1391        output. Unfortunately, the structure contains a field that has a different
1392        size on different hardware architectures. This meant that the tests that
1393        showed this size failed. As the block is currently always of a fixed size,
1394        this information isn't actually particularly useful in pcretest output, so
1395        I have just removed it.
1396    
1397     8. Three pre-processor statements accidentally did not start in column 1.
1398        Sadly, there are *still* compilers around that complain, even though
1399        standard C has not required this for well over a decade. Sigh.
1400    
1401     9. In pcretest, the code for checking callouts passed small integers in the
1402        callout_data field, which is a void * field. However, some picky compilers
1403        complained about the casts involved for this on 64-bit systems. Now
1404        pcretest passes the address of the small integer instead, which should get
1405        rid of the warnings.
1406    
1407    10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
1408        both compile and run time, and gives an error if an invalid UTF-8 sequence
1409        is found. There is a option for disabling this check in cases where the
1410        string is known to be correct and/or the maximum performance is wanted.
1411    
1412    11. In response to a bug report, I changed one line in Makefile.in from
1413    
1414            -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
1415        to
1416            -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
1417    
1418        to look similar to other lines, but I have no way of telling whether this
1419        is the right thing to do, as I do not use Windows. No doubt I'll get told
1420        if it's wrong...
1421    
1422    
1423    Version 4.3 21-May-03
1424    ---------------------
1425    
1426    1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
1427       Makefile.
1428    
1429    2. Some refactoring to improve the quality of the code:
1430    
1431       (i)   The utf8_table... variables are now declared "const".
1432    
1433       (ii)  The code for \cx, which used the "case flipping" table to upper case
1434             lower case letters, now just substracts 32. This is ASCII-specific,
1435             but the whole concept of \cx is ASCII-specific, so it seems
1436             reasonable.
1437    
1438       (iii) PCRE was using its character types table to recognize decimal and
1439             hexadecimal digits in the pattern. This is silly, because it handles
1440             only 0-9, a-f, and A-F, but the character types table is locale-
1441             specific, which means strange things might happen. A private
1442             table is now used for this - though it costs 256 bytes, a table is
1443             much faster than multiple explicit tests. Of course, the standard
1444             character types table is still used for matching digits in subject
1445             strings against \d.
1446    
1447       (iv)  Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
1448             ending in _t are). So I've renamed it as ESC_tee.
1449    
1450    3. The first argument for regexec() in the POSIX wrapper should have been
1451       defined as "const".
1452    
1453    4. Changed pcretest to use malloc() for its buffers so that they can be
1454       Electric Fenced for debugging.
1455    
1456    5. There were several places in the code where, in UTF-8 mode, PCRE would try
1457       to read one or more bytes before the start of the subject string. Often this
1458       had no effect on PCRE's behaviour, but in some circumstances it could
1459       provoke a segmentation fault.
1460    
1461    6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
1462       to try to read one or more bytes before the start of the subject string.
1463    
1464    7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
1465       UTF-8 support could misbehave in various ways if the subject string
1466       contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
1467       area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
1468       back over UTF-8 characters.)
1469    
1470    
1471    Version 4.2 14-Apr-03
1472    ---------------------
1473    
1474    1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
1475    
1476    2. Changes to the building process, supplied by Ronald Landheer-Cieslak
1477         [ON_WINDOWS]: new variable, "#" on non-Windows platforms
1478         [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
1479         [WIN_PREFIX]: new variable, "cyg" for Cygwin
1480         * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
1481           and BUILD_EXEEXT
1482         Note: automatic setting of the BUILD variables is not yet working
1483         set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
1484           compile-time but not at link-time
1485         [LINK]: use for linking executables only
1486         make different versions for Windows and non-Windows
1487         [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
1488           libraries
1489         [LINK_FOR_BUILD]: new variable
1490         [OBJEXT]: use throughout
1491         [EXEEXT]: use throughout
1492         <winshared>: new target
1493         <wininstall>: new target
1494         <dftables.o>: use native compiler
1495         <dftables>: use native linker
1496         <install>: handle Windows platform correctly
1497         <clean>: ditto
1498         <check>: ditto
1499         copy DLL to top builddir before testing
1500    
1501       As part of these changes, -no-undefined was removed again. This was reported
1502       to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
1503       in any case.
1504    
1505    3. Some tidies to get rid of compiler warnings:
1506    
1507       . In the match_data structure, match_limit was an unsigned long int, whereas
1508         match_call_count was an int. I've made them both unsigned long ints.
1509    
1510       . In pcretest the fact that a const uschar * doesn't automatically cast to
1511         a void * provoked a warning.
1512    
1513       . Turning on some more compiler warnings threw up some "shadow" variables
1514         and a few more missing casts.
1515    
1516    4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
1517       option, a class that contained a single character with a value between 128
1518       and 255 (e.g. /[\xFF]/) caused PCRE to crash.
1519    
1520    5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
1521       option, a class that contained several characters, but with at least one
1522       whose value was between 128 and 255 caused PCRE to crash.
1523    
1524    
1525    Version 4.1 12-Mar-03
1526    ---------------------
1527    
1528    1. Compiling with gcc -pedantic found a couple of places where casts were
1529    needed, and a string in dftables.c that was longer than standard compilers are
1530    required to support.
1531    
1532    2. Compiling with Sun's compiler found a few more places where the code could
1533    be tidied up in order to avoid warnings.
1534    
1535    3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
1536    first of these names is deprecated in the latest Autoconf in favour of the name
1537    CC_FOR_BUILD, because "host" is typically used to mean the system on which the
1538    compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
1539    analogy I have changed it to CFLAGS_FOR_BUILD.
1540    
1541    4. Added -no-undefined to the linking command in the Makefile, because this is
1542    apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
1543    linking step for the pcreposix library.
1544    
1545    5. PCRE was failing to diagnose the case of two named groups with the same
1546    name.
1547    
1548    6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
1549    literal character that is needed in the subject for a match, and scans along to
1550    ensure that it is present before embarking on the full matching process. This
1551    saves time in cases of nested unlimited repeats that are never going to match.
1552    Problem: the scan can take a lot of time if the subject is very long (e.g.
1553    megabytes), thus penalizing straightforward matches. It is now done only if the
1554    amount of subject to be scanned is less than 1000 bytes.
1555    
1556    7. A lesser problem with the same optimization is that it was recording the
1557    first character of an anchored pattern as "needed", thus provoking a search
1558    right along the subject, even when the first match of the pattern was going to
1559    fail. The "needed" character is now not set for anchored patterns, unless it
1560    follows something in the pattern that is of non-fixed length. Thus, it still
1561    fulfils its original purpose of finding quick non-matches in cases of nested
1562    unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
1563    
1564    
1565    Version 4.0 17-Feb-03
1566    ---------------------
1567    
1568    1. If a comment in an extended regex that started immediately after a meta-item
1569    extended to the end of string, PCRE compiled incorrect data. This could lead to
1570    all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
1571    
1572    2. Moved to autoconf 2.53 and libtool 1.4.2.
1573    
1574    3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
1575    the special perltest8 script is no longer needed - all the tests can be run
1576    from a single perltest script.
1577    
1578    4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
1579    by \s. It has now been removed in PCRE. This means it isn't recognized as
1580    whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
1581    class [:space:] *does* include VT, thereby creating a mess.
1582    
1583    5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
1584    space and tab.
1585    
1586    6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
1587    its new features into the main test script, reducing the number of scripts.
1588    
1589    7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
1590    were backward compatible, and made the (?i) apply to the whole pattern, as if
1591    /i were given. Now it behaves more logically, and applies the option setting
1592    only to what follows. PCRE has been changed to follow suit. However, if it
1593    finds options settings right at the start of the pattern, it extracts them into
1594    the global options, as before. Thus, they show up in the info data.
1595    
1596    8. Added support for the \Q...\E escape sequence. Characters in between are
1597    treated as literals. This is slightly different from Perl in that $ and @ are
1598    also handled as literals inside the quotes. In Perl, they will cause variable
1599    interpolation. Note the following examples:
1600    
1601        Pattern            PCRE matches      Perl matches
1602    
1603        \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
1604        \Qabc\$xyz\E       abc\$xyz          abc\$xyz
1605        \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
1606    
1607    For compatibility with Perl, \Q...\E sequences are recognized inside character
1608    classes as well as outside them.
1609    
1610    9. Re-organized 3 code statements in pcretest to avoid "overflow in
1611    floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
1612    (size_t) cast to one statement in pcretest and one in pcreposix to avoid
1613    signed/unsigned warnings.
1614    
1615    10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
1616    option for pcretest, so I've replaced it by a simple function that does just
1617    that job.
1618    
1619    11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
1620    "pcregrep -".
1621    
1622    12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
1623    Java package. This provides some syntactic sugar for simple cases of what my
1624    documentation calls "once-only subpatterns". A pattern such as x*+ is the same
1625    as (?>x*). In other words, if what is inside (?>...) is just a single repeated
1626    item, you can use this simplified notation. Note that only makes sense with
1627    greedy quantifiers. Consequently, the use of the possessive quantifier forces
1628    greediness, whatever the setting of the PCRE_UNGREEDY option.
1629    
1630    13. A change of greediness default within a pattern was not taking effect at
1631    the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
1632    subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
1633    was abstracted outside.
1634    
1635    14. PCRE now supports the \G assertion. It is true when the current matching
1636    position is at the start point of the match. This differs from \A when the
1637    starting offset is non-zero. Used with the /g option of pcretest (or similar
1638    code), it works in the same way as it does for Perl's /g option. If all
1639    alternatives of a regex begin with \G, the expression is anchored to the start
1640    match position, and the "anchored" flag is set in the compiled expression.
1641    
1642    15. Some bugs concerning the handling of certain option changes within patterns
1643    have been fixed. These applied to options other than (?ims). For example,
1644    "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
1645    been the other way round. Some of this was related to change 7 above.
1646    
1647    16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
1648    features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
1649    and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
1650    POSIX classes only within a class (e.g. /[[:alpha:]]/).
1651    
1652    17. Added support for Perl's \C escape. This matches one byte, even in UTF8
1653    mode. Unlike ".", it always matches newline, whatever the setting of
1654    PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
1655    assertions. Perl allows it, but it doesn't (in general) work because it can't
1656    calculate the length of the lookbehind. At least, that's the case for Perl
1657    5.8.0 - I've been told they are going to document that it doesn't work in
1658    future.
1659    
1660    18. Added an error diagnosis for escapes that PCRE does not support: these are
1661    \L, \l, \N, \P, \p, \U, \u, and \X.
1662    
1663    19. Although correctly diagnosing a missing ']' in a character class, PCRE was
1664    reading past the end of the pattern in cases such as /[abcd/.
1665    
1666    20. PCRE was getting more memory than necessary for patterns with classes that
1667    contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
1668    
1669    21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
1670    compiling PCRE for use with Virtual Pascal.
1671    
1672    22. Small fix to the Makefile to make it work properly if the build is done
1673    outside the source tree.
1674    
1675    23. Added a new extension: a condition to go with recursion. If a conditional
1676    subpattern starts with (?(R) the "true" branch is used if recursion has
1677    happened, whereas the "false" branch is used only at the top level.
1678    
1679    24. When there was a very long string of literal characters (over 255 bytes
1680    without UTF support, over 250 bytes with UTF support), the computation of how
1681    much memory was required could be incorrect, leading to segfaults or other
1682    strange effects.
1683    
1684    25. PCRE was incorrectly assuming anchoring (either to start of subject or to
1685    start of line for a non-DOTALL pattern) when a pattern started with (.*) and
1686    there was a subsequent back reference to those brackets. This meant that, for
1687    example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
1688    possible to check for precisely this case. All we can do is abandon the
1689    optimization if .* occurs inside capturing brackets when there are any back
1690    references whatsoever. (See below for a better fix that came later.)
1691    
1692    26. The handling of the optimization for finding the first character of a
1693    non-anchored pattern, and for finding a character that is required later in the
1694    match were failing in some cases. This didn't break the matching; it just
1695    failed to optimize when it could. The way this is done has been re-implemented.
1696    
1697    27. Fixed typo in error message for invalid (?R item (it said "(?p").
1698    
1699    28. Added a new feature that provides some of the functionality that Perl
1700    provides with (?{...}). The facility is termed a "callout". The way it is done
1701    in PCRE is for the caller to provide an optional function, by setting
1702    pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
1703    global variable. By default it is unset, which disables all calling out. To get
1704    the function called, the regex must include (?C) at appropriate points. This
1705    is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
1706    This provides a means of identifying different callout points. When PCRE
1707    reaches such a point in the regex, if pcre_callout has been set, the external
1708    function is called. It is provided with data in a structure called
1709    pcre_callout_block, which is defined in pcre.h. If the function returns 0,
1710    matching continues; if it returns a non-zero value, the match at the current
1711    point fails. However, backtracking will occur if possible. [This was changed
1712    later and other features added - see item 49 below.]
1713    
1714    29. pcretest is upgraded to test the callout functionality. It provides a
1715    callout function that displays information. By default, it shows the start of
1716    the match and the current position in the text. There are some new data escapes
1717    to vary what happens:
1718    
1719        \C+         in addition, show current contents of captured substrings
1720        \C-         do not supply a callout function
1721        \C!n        return 1 when callout number n is reached
1722        \C!n!m      return 1 when callout number n is reached for the mth time
1723    
1724    30. If pcregrep was called with the -l option and just a single file name, it
1725    output "<stdin>" if a match was found, instead of the file name.
1726    
1727    31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
1728    slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
1729    pcre_exec(). This saves a malloc/free per call. The default value of
1730    POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
1731    when configuring.
1732    
1733    32. The default maximum size of a compiled pattern is 64K. There have been a
1734    few cases of people hitting this limit. The code now uses macros to handle the
1735    storing of links as offsets within the compiled pattern. It defaults to 2-byte
1736    links, but this can be changed to 3 or 4 bytes by --with-link-size when
1737    configuring. Tests 2 and 5 work only with 2-byte links because they output
1738    debugging information about compiled patterns.
1739    
1740    33. Internal code re-arrangements:
1741    
1742    (a) Moved the debugging function for printing out a compiled regex into
1743        its own source file (printint.c) and used #include to pull it into
1744        pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
1745        separate copies.
1746    
1747    (b) Defined the list of op-code names for debugging as a macro in
1748        internal.h so that it is next to the definition of the opcodes.
1749    
1750    (c) Defined a table of op-code lengths for simpler skipping along compiled
1751        code. This is again a macro in internal.h so that it is next to the
1752        definition of the opcodes.
1753    
1754    34. Added support for recursive calls to individual subpatterns, along the
1755    lines of Robin Houston's patch (but implemented somewhat differently).
1756    
1757    35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
1758    allow it to read and process whole directories in Win32. This code was
1759    contributed by Lionel Fourquaux; it has not been tested by me.
1760    
1761    36. Added support for named subpatterns. The Python syntax (?P<name>...) is
1762    used to name a group. Names consist of alphanumerics and underscores, and must
1763    be unique. Back references use the syntax (?P=name) and recursive calls use
1764    (?P>name) which is a PCRE extension to the Python extension. Groups still have
1765    numbers. The function pcre_fullinfo() can be used after compilation to extract
1766    a name/number map. There are three relevant calls:
1767    
1768      PCRE_INFO_NAMEENTRYSIZE        yields the size of each entry in the map
1769      PCRE_INFO_NAMECOUNT            yields the number of entries
1770      PCRE_INFO_NAMETABLE            yields a pointer to the map.
1771    
1772    The map is a vector of fixed-size entries. The size of each entry depends on
1773    the length of the longest name used. The first two bytes of each entry are the
1774    group number, most significant byte first. There follows the corresponding
1775    name, zero terminated. The names are in alphabetical order.
1776    
1777    37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
1778    case instead of 255. Making it the same both with and without UTF-8 support
1779    means that the same test output works with both.
1780    
1781    38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
1782    calling malloc() with a zero argument.
1783    
1784    39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
1785    optimization. I've improved things by keeping a bitmap of backreferences with
1786    numbers 1-31 so that if .* occurs inside capturing brackets that are not in
1787    fact referenced, the optimization can be applied. It is unlikely that a
1788    relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
1789    the match to follow \n) will appear inside brackets with a number greater than
1790    31, but if it does, any back reference > 31 suppresses the optimization.
1791    
1792    40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
1793    of disabling numbered capturing parentheses. Any opening parenthesis that is
1794    not followed by ? behaves as if it were followed by ?: but named parentheses
1795    can still be used for capturing (and they will acquire numbers in the usual
1796    way).
1797    
1798    41. Redesigned the return codes from the match() function into yes/no/error so
1799    that errors can be passed back from deep inside the nested calls. A malloc
1800    failure while inside a recursive subpattern call now causes the
1801    PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
1802    
1803    42. It is now possible to set a limit on the number of times the match()
1804    function is called in a call to pcre_exec(). This facility makes it possible to
1805    limit the amount of recursion and backtracking, though not in a directly
1806    obvious way, because the match() function is used in a number of different
1807    circumstances. The count starts from zero for each position in the subject
1808    string (for non-anchored patterns). The default limit is, for compatibility, a
1809    large number, namely 10 000 000. You can change this in two ways:
1810    
1811    (a) When configuring PCRE before making, you can use --with-match-limit=n
1812        to set a default value for the compiled library.
1813    
1814    (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
1815        a different value is set. See 45 below.
1816    
1817    If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
1818    
1819    43. Added a new function pcre_config(int, void *) to enable run-time extraction
1820    of things that can be changed at compile time. The first argument specifies
1821    what is wanted and the second points to where the information is to be placed.
1822    The current list of available information is:
1823    
1824      PCRE_CONFIG_UTF8
1825    
1826    The output is an integer that is set to one if UTF-8 support is available;
1827    otherwise it is set to zero.
1828    
1829      PCRE_CONFIG_NEWLINE
1830    
1831    The output is an integer that it set to the value of the code that is used for
1832    newline. It is either LF (10) or CR (13).
1833    
1834      PCRE_CONFIG_LINK_SIZE
1835    
1836    The output is an integer that contains the number of bytes used for internal
1837    linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
1838    
1839      PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
1840    
1841    The output is an integer that contains the threshold above which the POSIX
1842    interface uses malloc() for output vectors. See item 31 above.
1843    
1844      PCRE_CONFIG_MATCH_LIMIT
1845    
1846    The output is an unsigned integer that contains the default limit of the number
1847    of match() calls in a pcre_exec() execution. See 42 above.
1848    
1849    44. pcretest has been upgraded by the addition of the -C option. This causes it
1850    to extract all the available output from the new pcre_config() function, and to
1851    output it. The program then exits immediately.
1852    
1853    45. A need has arisen to pass over additional data with calls to pcre_exec() in
1854    order to support additional features. One way would have been to define
1855    pcre_exec2() (for example) with extra arguments, but this would not have been
1856    extensible, and would also have required all calls to the original function to
1857    be mapped to the new one. Instead, I have chosen to extend the mechanism that
1858    is used for passing in "extra" data from pcre_study().
1859    
1860    The pcre_extra structure is now exposed and defined in pcre.h. It currently
1861    contains the following fields:
1862    
1863      flags         a bitmap indicating which of the following fields are set
1864      study_data    opaque data from pcre_study()
1865      match_limit   a way of specifying a limit on match() calls for a specific
1866                      call to pcre_exec()
1867      callout_data  data for callouts (see 49 below)
1868    
1869    The flag bits are also defined in pcre.h, and are
1870    
1871      PCRE_EXTRA_STUDY_DATA
1872      PCRE_EXTRA_MATCH_LIMIT
1873      PCRE_EXTRA_CALLOUT_DATA
1874    
1875    The pcre_study() function now returns one of these new pcre_extra blocks, with
1876    the actual study data pointed to by the study_data field, and the
1877    PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
1878    before. That is, this change is entirely upwards-compatible and requires no
1879    change to existing code.
1880    
1881    If you want to pass in additional data to pcre_exec(), you can either place it
1882    in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
1883    block.
1884    
1885    46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
1886    data string contains the escape sequence \M, pcretest calls pcre_exec() several
1887    times with different match limits, until it finds the minimum value needed for
1888    pcre_exec() to complete. The value is then output. This can be instructive; for
1889    most simple matches the number is quite small, but for pathological cases it
1890    gets very large very quickly.
1891    
1892    47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
1893    returns the size of the data block pointed to by the study_data field in a
1894    pcre_extra block, that is, the value that was passed as the argument to
1895    pcre_malloc() when PCRE was getting memory in which to place the information
1896    created by pcre_study(). The fourth argument should point to a size_t variable.
1897    pcretest has been extended so that this information is shown after a successful
1898    pcre_study() call when information about the compiled regex is being displayed.
1899    
1900    48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
1901    because what follows is always an absolute path. (Later: it turns out that this
1902    is more than cosmetic for MinGW, because it doesn't like empty path
1903    components.)
1904    
1905    49. Some changes have been made to the callout feature (see 28 above):
1906    
1907    (i)  A callout function now has three choices for what it returns:
1908    
1909           0  =>  success, carry on matching
1910         > 0  =>  failure at this point, but backtrack if possible
1911         < 0  =>  serious error, return this value from pcre_exec()
1912    
1913         Negative values should normally be chosen from the set of PCRE_ERROR_xxx
1914         values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
1915         "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
1916         use by callout functions. It will never be used by PCRE itself.
1917    
1918    (ii) The pcre_extra structure (see 45 above) has a void * field called
1919         callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
1920         pcre_callout_block structure has a field of the same name. The contents of
1921         the field passed in the pcre_extra structure are passed to the callout
1922         function in the corresponding field in the callout block. This makes it
1923         easier to use the same callout-containing regex from multiple threads. For
1924         testing, the pcretest program has a new data escape
1925    
1926           \C*n        pass the number n (may be negative) as callout_data
1927    
1928         If the callout function in pcretest receives a non-zero value as
1929         callout_data, it returns that value.
1930    
1931    50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
1932    there were some redundant $(CFLAGS) in commands that are now specified as
1933    $(LINK), which already includes $(CFLAGS).
1934    
1935    51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
1936    has been compiled with UTF-8 support *and* pcre_compile() has been compiled
1937    with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
1938    one-byte characters throughout. Note that case-insensitive matching applies
1939    only to characters whose values are less than 256. PCRE doesn't support the
1940    notion of cases for higher-valued characters.
1941    
1942    (i)   A character class whose characters are all within 0-255 is handled as
1943          a bit map, and the map is inverted for negative classes. Previously, a
1944          character > 255 always failed to match such a class; however it should
1945          match if the class was a negative one (e.g. [^ab]). This has been fixed.
1946    
1947    (ii)  A negated character class with a single character < 255 is coded as
1948          "not this character" (OP_NOT). This wasn't working properly when the test
1949          character was multibyte, either singly or repeated.
1950    
1951    (iii) Repeats of multibyte characters are now handled correctly in UTF-8
1952          mode, for example: \x{100}{2,3}.
1953    
1954    (iv)  The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
1955          singly or repeated) now correctly test multibyte characters. However,
1956          PCRE doesn't recognize any characters with values greater than 255 as
1957          digits, spaces, or word characters. Such characters always match \D, \S,
1958          and \W, and never match \d, \s, or \w.
1959    
1960    (v)   Classes may now contain characters and character ranges with values
1961          greater than 255. For example: [ab\x{100}-\x{400}].
1962    
1963    (vi)  pcregrep now has a --utf-8 option (synonym -u) which makes it call
1964          PCRE in UTF-8 mode.
1965    
1966    52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
1967    PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
1968    retained for backwards compatibility. (Note that LASTLITERAL is also a byte
1969    value.)
1970    
1971    53. The single man page has become too large. I have therefore split it up into
1972    a number of separate man pages. These also give rise to individual HTML pages;
1973    these are now put in a separate directory, and there is an index.html page that
1974    lists them all. Some hyperlinking between the pages has been installed.
1975    
1976    54. Added convenience functions for handling named capturing parentheses.
1977    
1978    55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
1979    aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
1980    true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
1981    are faulted.
1982    
1983    56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
1984    calling configure. These values are used when compiling the dftables.c program
1985    which is run to generate the source of the default character tables. They
1986    default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
1987    you will need to set these values.
1988    
1989    57. Updated the building process for Windows DLL, as provided by Fred Cox.
1990    
1991    
1992    Version 3.9 02-Jan-02
1993    ---------------------
1994    
1995    1. A bit of extraneous text had somehow crept into the pcregrep documentation.
1996    
1997    2. If --disable-static was given, the building process failed when trying to
1998    build pcretest and pcregrep. (For some reason it was using libtool to compile
1999    them, which is not right, as they aren't part of the library.)
2000    
2001    
2002    Version 3.8 18-Dec-01
2003    ---------------------
2004    
2005    1. The experimental UTF-8 code was completely screwed up. It was packing the
2006    bytes in the wrong order. How dumb can you get?
2007    
2008    
2009    Version 3.7 29-Oct-01
2010    ---------------------
2011    
2012    1. In updating pcretest to check change 1 of version 3.6, I screwed up.
2013    This caused pcretest, when used on the test data, to segfault. Unfortunately,
2014    this didn't happen under Solaris 8, where I normally test things.
2015    
2016    2. The Makefile had to be changed to make it work on BSD systems, where 'make'
2017    doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
2018    isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
2019    this fix an hour or so after the initial 3.7 release.)
2020    
2021    
2022    Version 3.6 23-Oct-01
2023    ---------------------
2024    
2025    1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
2026    offsets passed as NULL with zero offset count.
2027    
2028    2. The config.guess and config.sub files had not been updated when I moved to
2029    the latest autoconf.
2030    
2031    
2032    Version 3.5 15-Aug-01
2033    ---------------------
2034    
2035    1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
2036    had been forgotten.
2037    
2038    2. By using declared but undefined structures, we can avoid using "void"
2039    definitions in pcre.h while keeping the internal definitions of the structures
2040    private.
2041    
2042    3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
2043    user point of view, this means that both static and shared libraries are built
2044    by default, but this can be individually controlled. More of the work of
2045    handling this static/shared cases is now inside libtool instead of PCRE's make
2046    file.
2047    
2048    4. The pcretest utility is now installed along with pcregrep because it is
2049    useful for users (to test regexs) and by doing this, it automatically gets
2050    relinked by libtool. The documentation has been turned into a man page, so
2051    there are now .1, .txt, and .html versions in /doc.
2052    
2053    5. Upgrades to pcregrep:
2054       (i)   Added long-form option names like gnu grep.
2055       (ii)  Added --help to list all options with an explanatory phrase.
2056       (iii) Added -r, --recursive to recurse into sub-directories.
2057       (iv)  Added -f, --file to read patterns from a file.
2058    
2059    6. pcre_exec() was referring to its "code" argument before testing that
2060    argument for NULL (and giving an error if it was NULL).
2061    
2062    7. Upgraded Makefile.in to allow for compiling in a different directory from
2063    the source directory.
2064    
2065    8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
2066    options bits, the pointer it was passed was to an int instead of to an unsigned
2067    long int. This mattered only on 64-bit systems.
2068    
2069    9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
2070    generated) instead of pcre.in, which it its source. Also made the same change
2071    in several of the .c files.
2072    
2073    10. A new release of gcc defines printf() as a macro, which broke pcretest
2074    because it had an ifdef in the middle of a string argument for printf(). Fixed
2075    by using separate calls to printf().
2076    
2077    11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
2078    script, to force use of CR or LF instead of \n in the source. On non-Unix
2079    systems, the value can be set in config.h.
2080    
2081    12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
2082    absolute limit. Changed the text of the error message to make this clear, and
2083    likewise updated the man page.
2084    
2085    13. The limit of 99 on the number of capturing subpatterns has been removed.
2086    The new limit is 65535, which I hope will not be a "real" limit.
2087    
2088    
2089    Version 3.4 22-Aug-00
2090    ---------------------
2091    
2092    1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
2093    
2094    2. Diagnose condition (?(0) as an error instead of crashing on matching.
2095    
2096    
2097    Version 3.3 01-Aug-00
2098    ---------------------
2099    
2100    1. If an octal character was given, but the value was greater than \377, it
2101    was not getting masked to the least significant bits, as documented. This could
2102    lead to crashes in some systems.
2103    
2104    2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
2105    the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
2106    
2107    3. Added the functions pcre_free_substring() and pcre_free_substring_list().
2108    These just pass their arguments on to (pcre_free)(), but they are provided
2109    because some uses of PCRE bind it to non-C systems that can call its functions,
2110    but cannot call free() or pcre_free() directly.
2111    
2112    4. Add "make test" as a synonym for "make check". Corrected some comments in
2113    the Makefile.
2114    
2115    5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
2116    Makefile.
2117    
2118    6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
2119    command called pgrep for grepping around the active processes.
2120    
2121    7. Added the beginnings of support for UTF-8 character strings.
2122    
2123    8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
2124    RANLIB to ./ltconfig so that they are used by libtool. I think these are all
2125    the relevant ones. (AR is not passed because ./ltconfig does its own figuring
2126    out for the ar command.)
2127    
2128    
2129  Version 3.2 12-May-00  Version 3.2 12-May-00
2130  ---------------------  ---------------------

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